Cartography is the design and production of maps, or visual representations of spatial data. In cartography, coordinate systems are used as references for locations on the Earth and/or on planar maps. For any given location on the Earth and for a given map display and scale, one or many of the more than 300 geographic coordinate systems and more than 2500 projected coordinate systems are available for use. A geographic coordinate system specifies a location on the Earth using three coordinates of a spherical coordinate system aligned with the sign axis of the Earth.
A projection is a two-dimensional representation of a three-dimensional area, and a projection may be implemented using any of the projected coordinate systems. The projected coordinate system defines one or more mathematical functions to translate the three-dimensional representation to a two-dimensional representation. For example, a projection may be used to represent the Earth, a three-dimensional object, as a planar surface, such as a map. Furthermore, flat maps require the use of map projections. Flat maps may be more useful than globes or other three-dimensional representations in many situations: they are more compact and easier to store; they readily accommodate a wide range of scales; and they are viewed easily on computer displays.
Many properties of the Earth's surface may be measured independent of its geography. For example, some properties of interest may be area, shape, direction, distance, and scale. Map projections may be constructed to preserve one or more of these properties, though not all of them simultaneously. Each projected coordinate system and the resulting map projection, preserves, compromises, or approximates the basic properties in different ways. The purpose of the map, then, determines which projected coordinate system should be utilized to generate the map projection.
A geographic information system (GIS) is a system for capturing, storing, analyzing, and managing data and associated attributes, which are spatially referenced to the earth. More generically, a GIS is a tool (e.g., a computer system) that allows users to interact with geographically-referenced information. GIS software has widespread applicability and is often used throughout science, government, business, and industry, with applications including real estate, public health, crime mapping, national defense, sustainable development, natural resources, transportation, and logistics. Furthermore, GIS software is especially pertinent to oil and gas exploration and drilling companies. Oil and gas companies may use a GIS along with geographic data to locate and explore potential drilling regions or to control operations in current oil or gas fields. Such companies demand accurate and consistent geographic data, as mistakes can be very costly in this industry.
Due to a lack of knowledgeable personnel or other resources, oil and gas companies typically use only a small percentage of the more than 2500 projected coordinate systems (e.g., sometimes less than 20). Moreover, current GIS based applications do not typically support real-time adjustments to a projected map's projected coordinate system (e.g., based on a set of applicable map projections). As a result, sub-optimal selections of projected coordinate systems for different portions of the Earth are made, causing inaccurate measurements of shape, area, distance, and directions on the map projection. Additionally, the use of incorrect or inconsistent map projections may lead to drilling operations (e.g., drilling a wellbore) being carried out several hundred meters from a desired location.